SKU (pronounced as skew) in the field of inventory management stands for a stock keeping unit.
It is used as a listing and variation identifier.
By setting SKUs to all of your listings and variations you can easily track and manage your stock between both stores.
As mentioned, SKU will be used as your listing and variation identifier. Although you can set incremental numbers, It is best to set a meaningful naming so you will be able to search, find and manage your SKUs.
For example listing named "Red Shirt" with 3 size variations the SKUs can be set
Duplicate SKUs - can you reuse the same SKU in multiple variations and listings ?
You may want to use the same listing in multiple categories for example in "best seller" and "sales". That means that when an order comes in with this SKU shopUpz will go over all of your duplicate SKUs and update the quantity accordingly.
Duplicate SKUs limitations
When using shopUpz Inventory you can set the same SKU on different listings. That said, you can NOT use the same SKU in the same listing variations.